:root {
  --blue: #3caaf6;
  --blue-dark: #1a86e0;
  --navy: #0b2545;
  --ink: #1d3349;
  --muted: #5f7488;
  --line: #e4edf5;
  --bg-soft: #f5f9fd;
  --radius: 10px;
  --shadow: 0 6px 24px rgba(11, 37, 69, 0.08);
  --shadow-lg: 0 16px 44px rgba(11, 37, 69, 0.14);
  --maxw: 1220px;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Segoe UI", Roboto, Arial, sans-serif;
  color: var(--ink);
  line-height: 1.75;
  font-size: 16px;
  background: #fff;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { margin: 0; padding: 0; list-style: none; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }
.section { padding: 74px 0; }
.section--soft { background: var(--bg-soft); }
.section--navy { background: var(--navy); color: #fff; }

.sec-head { text-align: center; margin-bottom: 40px; }
.sec-head h2 { font-size: 30px; margin: 0 0 8px; letter-spacing: 1px; }
.sec-head .en { text-transform: uppercase; letter-spacing: 3px; font-size: 13px; color: var(--muted); margin: 0 0 14px; }
.sec-head .bar { width: 52px; height: 3px; background: var(--blue); margin: 0 auto; border-radius: 2px; }
.sec-head p.lead { max-width: 780px; margin: 16px auto 0; color: var(--muted); }
.section--navy .sec-head .en, .section--navy .sec-head p.lead { color: rgba(255, 255, 255, 0.72); }

/* ---------- header ---------- */
.hd {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, 0.97);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(8px);
}
.hd__in { display: flex; align-items: center; gap: 22px; height: 78px; }
.hd__logo img { height: 44px; width: auto; }
.hd__nav { display: flex; align-items: center; gap: 4px; margin-left: auto; }
.hd__nav > li > a {
  display: block; padding: 8px 14px; border-radius: 6px;
  font-size: 16px; font-weight: 500; color: var(--ink);
}
.hd__nav > li > a:hover, .hd__nav > li > a.on { color: var(--blue-dark); background: #f0f8ff; }
.has-sub { position: relative; }
.sub {
  position: absolute; left: 0; top: 100%; padding: 8px 0; min-width: 216px;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow-lg); opacity: 0; visibility: hidden; transform: translateY(8px);
  transition: 0.18s;
}
.has-sub:hover .sub, .has-sub:focus-within .sub { opacity: 1; visibility: visible; transform: translateY(0); }
.sub a { display: block; padding: 9px 18px; font-size: 15px; color: var(--ink); white-space: nowrap; }
.sub a:hover { color: var(--blue-dark); background: var(--bg-soft); }
.hd__tel { display: flex; flex-direction: column; align-items: flex-end; padding-left: 20px; border-left: 1px solid var(--line); }
.hd__tel b { color: var(--blue-dark); font-size: 20px; line-height: 1.2; letter-spacing: 0.5px; }
.hd__tel span { font-size: 12px; color: var(--muted); }
.lang { display: inline-flex; align-items: center; gap: 6px; margin-left: 14px; font-size: 14px; color: var(--muted); }
.lang a { padding: 5px 10px; border: 1px solid var(--line); border-radius: 20px; white-space: nowrap; }
.lang a.on { background: var(--blue); border-color: var(--blue); color: #fff; }
.burger { display: none; margin-left: auto; background: none; border: 1px solid var(--line); border-radius: 8px; padding: 9px 12px; font-size: 18px; cursor: pointer; }

/* ---------- hero ---------- */
.hero { position: relative; height: 610px; overflow: hidden; background: var(--navy); }
.hero__slide {
  position: absolute; inset: 0; opacity: 0; transition: opacity 0.9s ease;
  background-size: cover; background-position: center;
}
.hero__slide.on { opacity: 1; }
.hero__slide::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(90deg, rgba(7, 27, 51, 0.85) 0%, rgba(7, 27, 51, 0.55) 48%, rgba(7, 27, 51, 0.2) 100%);
}
.hero__body { position: relative; z-index: 2; height: 100%; display: flex; flex-direction: column; justify-content: center; color: #fff; max-width: 700px; }
.hero__body > * { opacity: 0; transform: translateY(14px); transition: 0.5s; }
.hero__slide.on .hero__body > * { opacity: 1; transform: none; }
.hero__kicker { font-size: 15px; letter-spacing: 4px; text-transform: uppercase; color: var(--blue); margin-bottom: 14px; }
.hero__title { font-size: 46px; line-height: 1.25; margin: 0 0 14px; font-weight: 700; }
.hero__sub { font-size: 20px; color: rgba(255, 255, 255, 0.88); margin: 0 0 26px; }
.hero__tags { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 30px; }
.hero__tags span { border: 1px solid rgba(255, 255, 255, 0.4); border-radius: 22px; padding: 5px 15px; font-size: 14px; background: rgba(255, 255, 255, 0.08); }
.hero__dots { position: absolute; bottom: 26px; left: 0; right: 0; z-index: 3; display: flex; justify-content: center; gap: 10px; }
.hero__dots button { width: 34px; height: 4px; border: 0; border-radius: 3px; background: rgba(255, 255, 255, 0.4); cursor: pointer; padding: 0; }
.hero__dots button.on { background: var(--blue); }

/* ---------- buttons ---------- */
.btn {
  display: inline-block; padding: 12px 30px; border-radius: 30px; font-size: 16px;
  background: var(--blue); color: #fff; transition: 0.2s; border: 1px solid var(--blue);
}
.btn:hover { background: var(--blue-dark); border-color: var(--blue-dark); }
.btn--ghost { background: transparent; color: var(--ink); border-color: #c9dcea; }
.btn--ghost:hover { color: var(--blue-dark); border-color: var(--blue); background: #f2f9ff; }
.btn--light { background: #fff; color: var(--navy); border-color: #fff; }
.btn--light:hover { background: var(--blue); color: #fff; border-color: var(--blue); }
.btn--sm { padding: 8px 20px; font-size: 14px; }

/* ---------- product line cards ---------- */
.grid-lines { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.line-card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; transition: 0.22s; display: flex; flex-direction: column; }
.line-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: #cfe6f8; }
.line-card__img { aspect-ratio: 16 / 10; overflow: hidden; background: var(--bg-soft); }
.line-card__img img { width: 100%; height: 100%; object-fit: cover; transition: 0.4s; }
.line-card:hover .line-card__img img { transform: scale(1.05); }
.line-card__body { padding: 20px 22px 24px; display: flex; flex-direction: column; flex: 1; }
.line-card__body h3 { margin: 0 0 4px; font-size: 20px; }
.line-card__body .en { font-size: 12px; letter-spacing: 1.5px; text-transform: uppercase; color: var(--muted); margin-bottom: 10px; }
.line-card__body p { margin: 0 0 16px; color: var(--muted); font-size: 15px; flex: 1; }
.line-card__more { color: var(--blue-dark); font-size: 15px; }

/* ---------- about split ---------- */
.split { display: grid; grid-template-columns: 1.05fr 1fr; gap: 46px; align-items: center; }
.split--rev .split__img { order: 2; }
.split__img img { border-radius: var(--radius); box-shadow: var(--shadow); width: 100%; object-fit: cover; }
.split__txt h2 { font-size: 28px; margin: 0 0 6px; }
.split__txt .en { text-transform: uppercase; letter-spacing: 3px; color: var(--muted); font-size: 13px; margin: 0 0 18px; }
.split__txt p { color: var(--muted); margin: 0 0 14px; }
.split__txt .bar { width: 52px; height: 3px; background: var(--blue); border-radius: 2px; margin: 0 0 22px; }
.chips { display: flex; flex-wrap: wrap; gap: 12px; margin: 22px 0 26px; }
.chip { background: var(--bg-soft); border: 1px solid var(--line); border-radius: 8px; padding: 10px 16px; font-size: 15px; color: var(--ink); }
.chip b { color: var(--blue-dark); }

.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; margin-top: 46px; }
.stat { text-align: center; padding: 22px 10px; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); }
.stat b { display: block; font-size: 32px; color: var(--blue-dark); line-height: 1.2; }
.stat span { font-size: 14px; color: var(--muted); }

/* ---------- case cards ---------- */
.grid-cases { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.case { border-radius: var(--radius); overflow: hidden; position: relative; background: var(--navy); }
.case img { width: 100%; aspect-ratio: 4 / 3; object-fit: cover; opacity: 0.92; transition: 0.35s; }
.case:hover img { opacity: 0.62; transform: scale(1.04); }
.case figcaption { position: absolute; left: 0; right: 0; bottom: 0; padding: 12px 14px; color: #fff; font-size: 15px; background: linear-gradient(transparent, rgba(6, 22, 40, 0.9)); }
.case figcaption small { display: block; color: rgba(255, 255, 255, 0.7); font-size: 12px; }

/* ---------- process ---------- */
.steps { display: grid; grid-template-columns: repeat(7, 1fr); gap: 12px; }
.step { text-align: center; padding: 18px 8px; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); }
.step b { display: block; color: var(--blue); font-size: 20px; }
.step span { font-size: 14px; color: var(--ink); }

/* ---------- series on product pages ---------- */
.page-hero { padding: 64px 0; color: #fff; background: linear-gradient(120deg, var(--navy), #14406e); position: relative; overflow: hidden; }
.page-hero__bg { position: absolute; inset: 0; background-size: cover; background-position: center right; opacity: 0.22; }
.page-hero h1 { position: relative; font-size: 34px; margin: 0 0 6px; }
.page-hero .en { position: relative; text-transform: uppercase; letter-spacing: 3px; font-size: 13px; color: rgba(255, 255, 255, 0.75); margin: 0 0 16px; }
.page-hero p { position: relative; max-width: 800px; margin: 0; color: rgba(255, 255, 255, 0.88); }
.crumbs { font-size: 14px; color: rgba(255, 255, 255, 0.7); margin-bottom: 18px; position: relative; }
.crumbs a:hover { color: #fff; }

.series { display: grid; grid-template-columns: 0.92fr 1.08fr; gap: 40px; align-items: start; padding: 46px 0; border-bottom: 1px solid var(--line); }
.series:last-child { border-bottom: 0; }
.series--rev .series__media { order: 2; }
.series__media { position: sticky; top: 100px; }
.series__img { border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; background: #fff; }
.series__img { display: flex; align-items: center; justify-content: center; min-height: 220px; }
.series__img img { max-width: 100%; max-height: 560px; width: auto; height: auto; }
.series__img--wide { margin-top: 14px; }
.series__img--wide img { aspect-ratio: 16 / 7; object-fit: cover; }
.series__txt h2 { font-size: 25px; margin: 0 0 4px; }
.series__txt .model-line { color: var(--blue-dark); font-size: 15px; margin: 0 0 14px; font-weight: 500; }
.series__txt .sum { color: var(--muted); margin: 0 0 18px; }
.feat { display: grid; grid-template-columns: 1fr 1fr; gap: 8px 20px; margin: 0 0 22px; }
.feat li { position: relative; padding-left: 20px; font-size: 15px; }
.feat li::before { content: ""; position: absolute; left: 0; top: 11px; width: 8px; height: 8px; border-radius: 2px; background: var(--blue); }
.spec { width: 100%; border-collapse: collapse; font-size: 15px; }
.spec caption { text-align: left; font-weight: 600; padding-bottom: 8px; color: var(--ink); }
.spec th, .spec td { border: 1px solid var(--line); padding: 9px 12px; text-align: left; vertical-align: top; }
.spec th { width: 42%; font-weight: 500; color: var(--muted); background: var(--bg-soft); }
.spec tr:hover td { background: #f7fbff; }
.specs-tabs { margin-bottom: 18px; }
.app-tag { display: inline-block; background: #eef7ff; border: 1px solid #cfe6f8; color: var(--blue-dark); border-radius: 6px; padding: 4px 12px; font-size: 14px; margin: 0 8px 8px 0; }

.line-nav { display: flex; flex-wrap: wrap; gap: 10px; padding: 18px 0 0; border-top: 1px solid var(--line); }
.line-nav a { border: 1px solid var(--line); border-radius: 24px; padding: 7px 18px; font-size: 15px; color: var(--ink); }
.line-nav a:hover { border-color: var(--blue); color: var(--blue-dark); background: #f2f9ff; }

/* ---------- about page ---------- */
.grid-values { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.value { background: #fff; border: 1px solid var(--line); border-left: 3px solid var(--blue); border-radius: var(--radius); padding: 24px 26px; }
.value h3 { margin: 0 0 4px; font-size: 19px; }
.value .en { font-size: 12px; letter-spacing: 2px; text-transform: uppercase; color: var(--muted); margin: 0 0 12px; }
.value p { margin: 0; color: var(--muted); font-size: 15px; }
.grid-certs { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; max-width: 860px; margin: 0 auto; }
.cert { border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; background: #fff; }
.cert img { width: 100%; height: auto; }
.cert figcaption { padding: 14px 18px; font-size: 15px; color: var(--ink); border-top: 1px solid var(--line); }
.timeline { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.mile { border-top: 2px solid var(--blue); padding-top: 14px; }
.mile b { display: block; font-size: 22px; color: var(--blue-dark); }

/* ---------- contact ---------- */
.grid-contact { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.ccard { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; }
.ccard h3 { margin: 0 0 10px; font-size: 18px; }
.ccard .en { font-size: 12px; letter-spacing: 2px; text-transform: uppercase; color: var(--muted); margin: 0 0 14px; }
.ccard p { margin: 0 0 8px; color: var(--ink); }
.ccard a:hover { color: var(--blue-dark); }
.form { display: grid; gap: 14px; max-width: 760px; margin: 0 auto; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.form label { font-size: 14px; color: var(--muted); display: block; margin-bottom: 6px; }
.form input, .form textarea {
  width: 100%; padding: 11px 14px; border: 1px solid #cfdfeb; border-radius: 8px;
  font: inherit; font-size: 15px; color: var(--ink); background: #fff;
}
.form input:focus, .form textarea:focus { outline: none; border-color: var(--blue); box-shadow: 0 0 0 3px rgba(60, 170, 246, 0.14); }
.form textarea { min-height: 128px; resize: vertical; }
.note { font-size: 14px; color: var(--muted); background: var(--bg-soft); border: 1px dashed #cfe0ef; border-radius: 8px; padding: 12px 16px; }

/* ---------- cta band ---------- */
.cta { display: flex; align-items: center; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
.cta h2 { margin: 0 0 6px; font-size: 26px; }
.cta p { margin: 0; color: rgba(255, 255, 255, 0.8); }

/* ---------- footer ---------- */
.ft { background: var(--navy); color: rgba(255, 255, 255, 0.76); padding: 56px 0 0; font-size: 15px; }
.ft__grid { display: grid; grid-template-columns: 1.3fr repeat(3, 1fr) 1.1fr; gap: 30px; padding-bottom: 40px; }
.ft h4 { color: #fff; font-size: 16px; margin: 0 0 14px; }
.ft li { margin-bottom: 8px; }
.ft a:hover { color: var(--blue); }
.ft__brand img { height: 40px; margin-bottom: 14px; }
.ft__tel b { display: block; color: #fff; font-size: 25px; }
.ft__tel span { color: rgba(255, 255, 255, 0.6); font-size: 13px; }
.ft__bottom { border-top: 1px solid rgba(255, 255, 255, 0.12); padding: 18px 0; text-align: center; font-size: 13px; color: rgba(255, 255, 255, 0.55); }
.ft__bottom a { color: rgba(255, 255, 255, 0.65); }

/* ---------- floating contact ---------- */
.float { position: fixed; right: 16px; bottom: 96px; z-index: 60; display: flex; flex-direction: column; gap: 8px; }
.float a { background: var(--blue); color: #fff; border-radius: 8px; padding: 10px 14px; font-size: 14px; box-shadow: var(--shadow-lg); text-align: center; }
.float a:hover { background: var(--blue-dark); }

/* ---------- responsive ---------- */
@media (max-width: 1080px) {
  .grid-lines { grid-template-columns: repeat(2, 1fr); }
  .grid-cases { grid-template-columns: repeat(3, 1fr); }
  .steps { grid-template-columns: repeat(4, 1fr); }
  .ft__grid { grid-template-columns: 1fr 1fr 1fr; }
}
@media (max-width: 900px) {
  .hd__in { height: 66px; }
  .burger { display: block; }
  .hd__nav {
    position: fixed; left: 0; right: 0; top: 66px; flex-direction: column; align-items: stretch;
    background: #fff; border-bottom: 1px solid var(--line); padding: 10px 20px 18px; gap: 0;
    display: none; max-height: 76vh; overflow: auto;
  }
  .hd__nav.open { display: flex; }
  .hd__nav > li > a { padding: 12px 6px; border-bottom: 1px solid var(--line); }
  .hd__tel { display: none; }
  .lang { display: inline-flex; margin-left: auto; order: 2; }
  .burger { margin-left: 10px; order: 3; }
  .sub { position: static; opacity: 1; visibility: visible; transform: none; box-shadow: none; border: 0; padding: 0 0 0 14px; display: none; }
  .has-sub.open .sub { display: block; }
  .hero { height: auto; min-height: 460px; padding: 46px 0; }
  .hero__title { font-size: 30px; }
  .hero__sub { font-size: 17px; }
  .split, .series { grid-template-columns: 1fr; gap: 24px; }
  .series__media { position: static; }
  .split--rev .split__img { order: 0; }
  .grid-values, .grid-contact, .grid-certs, .timeline { grid-template-columns: 1fr; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .grid-cases { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .feat { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .ft__grid { grid-template-columns: 1fr 1fr; }
  .section { padding: 48px 0; }
  .sec-head h2 { font-size: 24px; }
  .float { bottom: 14px; right: 12px; }
  .float a:not(:first-child) { display: none; }
  .form { margin: 0 auto; }
}
@media (max-width: 520px) {
  .grid-cases, .stats, .steps { grid-template-columns: 1fr; }
  .hero__title { font-size: 26px; }
}

@media print { .hd, .ft, .float, .hero__dots { display: none; } }